<?php

/*
 * This file is part of SwiftMailer. (c) 2004-2009 Chris Corbyn For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 */

/**
 * A Date MIME Header for Swift Mailer.
 * 
 * @package Swift
 * @subpackage Mime
 * @author Chris Corbyn
 */
class Swift_Mime_Headers_DateHeader extends Swift_Mime_Headers_AbstractHeader {
	/**
	 * The UNIX timestamp value of this Header.
	 * 
	 * @var int
	 * @access private
	 */
	private $_timestamp;
	
	/**
	 * Creates a new DateHeader with $name and $timestamp.
	 * Example:
	 * <code>
	 * <?php
	 * $header = new Swift_Mime_Headers_DateHeader('Date', time());
	 * ?>
	 * </code>
	 * 
	 * @param string $name
	 *        	of Header
	 * @param Swift_Mime_Grammar $grammar        	
	 */
	public function __construct($name, Swift_Mime_Grammar $grammar) {
		$this->setFieldName ( $name );
		parent::__construct ( $grammar );
	}
	
	/**
	 * Get the type of Header that this instance represents.
	 * 
	 * @return int
	 * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
	 * @see TYPE_DATE, TYPE_ID, TYPE_PATH
	 */
	public function getFieldType() {
		return self::TYPE_DATE;
	}
	
	/**
	 * Set the model for the field body.
	 * This method takes a UNIX timestamp.
	 * 
	 * @param int $model        	
	 */
	public function setFieldBodyModel($model) {
		$this->setTimestamp ( $model );
	}
	
	/**
	 * Get the model for the field body.
	 * This method returns a UNIX timestamp.
	 * 
	 * @return mixed
	 */
	public function getFieldBodyModel() {
		return $this->getTimestamp ();
	}
	
	/**
	 * Get the UNIX timestamp of the Date in this Header.
	 * 
	 * @return int
	 */
	public function getTimestamp() {
		return $this->_timestamp;
	}
	
	/**
	 * Set the UNIX timestamp of the Date in this Header.
	 * 
	 * @param int $timestamp        	
	 */
	public function setTimestamp($timestamp) {
		if (! is_null ( $timestamp )) {
			$timestamp = ( int ) $timestamp;
		}
		$this->clearCachedValueIf ( $this->_timestamp != $timestamp );
		$this->_timestamp = $timestamp;
	}
	
	/**
	 * Get the string value of the body in this Header.
	 * This is not necessarily RFC 2822 compliant since folding white space will
	 * not be added at this stage (see {@link toString()} for that).
	 * 
	 * @return string
	 * @see toString()
	 */
	public function getFieldBody() {
		if (! $this->getCachedValue ()) {
			if (isset ( $this->_timestamp )) {
				$this->setCachedValue ( date ( 'r', $this->_timestamp ) );
			}
		}
		
		return $this->getCachedValue ();
	}
}
